Plasma stabilization method and plasma apparatus

ABSTRACT

A plasma technique in which a plasma generation technique frequently used in various fields including a semiconductor manufacturing process is used, and generation of plasma instability (high-speed impedance change of plasma) can efficiently be suppressed and controlled in order to manufacture stable products. An apparatus includes a processing chamber, a surrounding member disposed so as to surround the processing chamber, an RF induction coil disposed above the top surface, a direct-current magnetic field generator for supplying a direct-current magnetic field to the inner space, and an RF cut filter connected to a direct current (DC) power supply and connected to the direct-current magnetic field generator. The RF cut filter includes a first capacitor connected to a positive terminal of the DC power supply and to ground, and a second capacitor connected to a negative terminal of the DC power supply and to ground.

CLAIM OF PRIORITY

This application is a Divisional Application of U.S. patent applicationSer. No. 13/492,706 filed on Jun. 8, 2012, and entitled, “PLASMASTABILIZATION METHOD AND PLASMA APPARATUS”, which is a divisional ofU.S. application Ser. No. 11/999,708, filed on Dec. 5, 2007, (U.S. Pat.No. 8,216,421, issued on Jul. 10, 2012), which is a divisional of U.S.application Ser. No. 10/427,474, filed on Apr. 30, 2003 (U.S. Pat. No.7,320,941, issued on Jan. 22, 2008), all of which are incorporatedherein by reference.

BACKGROUND

1. Field of the Invention

The present invention relates to a processing method and apparatus for aplasma used for frequent use in processing of a semiconductor wafer, inmanufacturing an integrated circuit, or a plasma apparatus forperforming a plasma treatment.

2. Description of the Related Art

A treatment method using a plasma has heretofore been broadly usedbecause the method is very useful in various semiconductor manufacturingprocesses such as etching, resist removal, and vapor deposition. Forinductively coupled plasmas for generally frequent use, such as TCP andICP, a predetermined gas is passed through a chamber sealed by asurrounding member including a dielectric window member, and an RFcurrent, for example, of 13.56 MHz is passed through an RF inductioncoil disposed in the vicinity of the outside of the window member.Thereby, an electromagnetic field is generated in the chamber, and anelectron is accelerated and collides against a molecule so that an ionand radical are generated.

This ion and radical have a very high reactivity, and are frequentlyused in treatment processes such as plasma etching and plasmadeposition. The inductively coupled plasma has advantages such as that ahigh-density plasma can be generated, a large wafer area can be handled,and the induction coil does not contact the plasma without polluting anymetal. Therefore, the plasma still fulfils a most important function ina semiconductor manufacturing field.

However, electric and magnetic fields are simultaneously generated inthe inductively coupled plasma, and a drift is generated in theelectron. This brings the plasma into an unstable state, and aphenomenon called a plasma instability occurs. This is a probleminherent in this field. Moreover, when a reflected wave (reflectionpower) indicating a value not less than a predetermined value isgenerated because of the plasma instability, a manufactured product isvariously adversely affected. Here, problems caused by the plasmainstability in manufacturing semiconductor products such as anintegrated circuit will concretely be described. The problems includeinstability of a manufacturing process, damage to the product, decreasedyield, drop of operation ratio, differences generated amongmanufacturing apparatus, and the like.

Examples of conditions under which the plasma instability is generatedroughly include several factors such as a process gas type, gaspressure, and RF power. Even if optimum process conditions areestablished, the optimum process conditions have to be sometimes changedbecause of the plasma instability (reflection power generation).

Moreover, the plasma instability has not been fundamentally solved for along time since observed, and an effective method of suppressing theplasma instability has not yet been obtained.

SUMMARY

The present invention can be implemented in numerous ways, including asa process, an apparatus, a system, a device, a method, or a computerreadable media. Several embodiments of the present invention aredescribed below.

An object of the present invention is to provide a plasma technique inwhich a plasma generation technique broadly used in various fields suchas a semiconductor manufacturing process is used, and a plasmainstability is effectively inhibited from being generated and canfurther be controlled in order to steadily manufacture a satisfactoryproduct.

To solve the above-described problems and achieve the desired object, aplasma stabilization method and plasma apparatus according to thepresent invention are obtained by the following means.

In one embodiment, a plasma processing apparatus includes a processingchamber operable to process an object disposed within the processingchamber, a surrounding member disposed around the processing chamber, anRF induction coil disposed outside the dielectric member, and anair-core coil for generating a direct-current magnetic field supplied tothe inner space. The surrounding member seals an opening on top of theprocessing chamber and creates an inner space, the surrounding memberincluding a dielectric member, the surrounding member including a topsurface, a side surface, and a bottom surface. The RF induction coil isdisposed above the top surface, and the air-core coil is disposedoutside the side surface.

In another embodiment, a plasma processing apparatus includes aprocessing chamber operable to process an object disposed within theprocessing chamber, a surrounding member disposed around the processingchamber, an RF induction coil disposed outside the dielectric member,and a magnet for generating the direct-current magnetic field. Thesurrounding member seals an opening on top of the processing chamber andcreates an inner space, the surrounding member including a dielectricmember, the surrounding member including a top surface, a side surface,and a bottom surface. The RF induction coil is disposed above the topsurface, where a direct-current magnetic field is supplied to the innerspace, and the magnet is disposed outside the side surface.

In yet another embodiment, a plasma processing apparatus includes aprocessing chamber operable to process an object disposed within theprocessing chamber, a surrounding member disposed around the processingchamber, an RF induction coil disposed outside the dielectric member,and a structure operable to supply a direct-current magnetic field tothe inner space. The surrounding member seals an opening on top of theprocessing chamber and creates an inner space, the surrounding memberincluding a dielectric member. Further, the structure is a coil separatefrom the RF induction coil, and the structure is not a magnet.

In another embodiment, a plasma processing apparatus includes aprocessing chamber operable to process an object disposed within theprocessing chamber, a surrounding member disposed around the processingchamber, an RF induction coil disposed outside the dielectric member,and an air-core coil for generating the direct-current magnetic field.The surrounding member seales an opening on top of the processingchamber and creates an inner space, the surrounding member including adielectric member, the surrounding member including a top surface, aside surface, and a bottom surface. The RF induction coil is disposedabove the top surface, where a direct-current magnetic field is suppliedto the inner space, and, the air-core coil is disposed outside and abovethe top surface.

In one embodiment of the invention, a plasma stabilization method isdisclosed. In a plasma processing chamber, a plasma stabilization methodincludes sealing the plasma processing chamber with a surrounding memberto create an inner space. At least a part of the surrounding member isconstituted with a dielectric member. An RF induction coil is disposedoutside the dielectric member, and a direct-current magnetic field issupplied to the inner space with an apparatus in which a direct currentis passed through the RF induction coil to obtain the direct-currentmagnetic field.

In another embodiment, a plasma processing apparatus disclosed. Theplasma processing apparatus includes a processing chamber having anobject to be processed disposed within the processing chamber. Theplasma processing apparatus further includes a surrounding memberdisposed around the processing chamber. The surrounding member seals thechamber and creates an inner space and includes a dielectric member. Theplasma processing apparatus further includes an RF induction coil isdisposed outside the dielectric member. A direct-current magnetic fieldis supplied to the inner space by a structure in which a direct currentis passed through the RF induction coil to obtain the direct-currentmagnetic field.

In a further embodiment of the invention, a plasma processing chamber isdisclosed. In a plasma processing system for the processing ofsemiconductor wafers, a plasma processing chamber includes a surroundingmember disposed around the plasma processing chamber. The surroundingmember seals the plasma processing chamber and creates an inner space. Adielectric member constitutes at least a portion of the surroundingmember, and the dielectric member is configured as a quartz window. Theplasma processing chamber further includes an RF induction coil, and anRF cut filter through which direct current is supplied to the RFinduction coil.

With the use of the electromagnet, the plasma instability control caneffectively be performed, when the intensity, arrangement position andnumber, polarity, and the like of the magnet are appropriately changed.

Examples of a method of passing the direct current include: methods of(1) supplying a constant current; (2) controlling and supplying thecurrent in accordance with the plasma instability; and (3)intermittently supplying the current in order to suppress the plasmainstability beforehand.

Other advantages of the invention will become apparent from thefollowing detailed description, taken in conjunction with theaccompanying drawings, illustrating by way of example the principles ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute partof this specification, illustrate exemplary embodiments of the inventionand together with the description serve to explain the principles of theinvention.

FIG. 1 is a diagram of a plasma apparatus in which plasma instability bya direct-current magnetic field supply is improved, in accordance withone embodiment of the present invention.

FIG. 2 is a data graph obtained based on a conventional method orapparatus, in which a reflection power waveform to an RF power supplyduring generation of the plasma instability is shown, and detected by adirectional coupler of about −63 dB.

FIG. 3A is a schematic constitution diagram by a method of supplying anRF and direct current to an RF induction coil at the same time, inaccordance with one embodiment of the invention.

FIG. 3B is an electric circuit diagram of the apparatus shown in FIG.3A.

FIG. 4A is a graph showing a change of a magnetic flux density by adistance from the RF induction coil during the supplying of a directcurrent, in accordance with one embodiment of the invention.

FIG. 4B is a graph showing a supplied direct current and the change ofthe magnetic flux density in a position of 7 cm from the RF inductioncoil, in accordance with one embodiment of the present invention.

FIG. 5A is a graph showing a reflection power change to a supplieddirect-current magnetic flux change, in accordance with an embodiment ofthe invention.

FIG. 5B is a graph showing a reflection waveform during the supplying ofa direct-current magnetic field of 0 Gauss.

FIG. 5C is a graph showing the reflection waveform during the supplyingof a direct-current magnetic field of 4.3 Gausses, in accordance with anembodiment of the present invention.

FIG. 6A shows a constitution in which an air-core coil for thedirect-current magnetic field is disposed around a chamber, inaccordance with one embodiment of the present invention.

FIG. 6B shows a constitution in which the air-core coil for thedirect-current magnetic field is disposed around the chamber, inaccordance with an embodiment of the invention.

FIG. 6C shows that a magnet for the direct-current magnetic field isdisposed around the chamber, in accordance with an embodiment of thepresent invention.

FIG. 6D shows a constitution in which an electromagnet for thedirect-current magnetic field is disposed around the chamber, inaccordance with another embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Plasma stabilization methods and a plasma apparatus configured to effectplasma stabilization are described.

In the following description, numerous specific details are set forth inorder to provide a thorough understanding of the present invention. Itwill be understood, however, to one skilled in the art, that the presentinvention may be practiced without some or all of these specificdetails. In other instances, well known process operations have not beendescribed in detail in order not to unnecessarily obscure the presentinvention.

Embodiments of a plasma stabilization method and plasma apparatusaccording to the present invention will next be described in detail withreference to FIGS. 1 to 6.

A basic constitution of the plasma apparatus according to the presentinvention will be described with reference to FIG. 1. As shown in FIG.1, in the plasma apparatus, an object 16 is disposed on a lowerelectrode 14 inside a chamber 10, and the object 16 is treated by thegenerated plasma. The chamber 10 is closed by a surrounding memberincluding an upper surface portion 12, side surface portion 11 andbottom surface portion 13 so as to have an inner space 10′. Moreover, atleast a part of the surrounding member includes a dielectric material,but a dielectric window portion (quartz window) is disposed in the uppersurface portion 12 in FIG. 1, an RF induction coil 20 is disposedoutside (above) the dielectric member, and a direct current is passedthrough the RF induction coil 20 in a system (structure). Furthermore,in another system (structure), the direct-current magnetic field isobtained by a coil other than the RF induction coil or a magnet, so thatthe apparatus is constituted to supply a direct-current electric fieldto the inner space 10′. Here, Φ_(DC) indicates a flow of direct-currentmagnetic flux by the direct current, the flow passes through the uppersurface portion 12, and an arrow is directed in one direction (downwardsin the drawing). Moreover, Φ_(RF) indicates an RF magnetic flux by theRF current supplied from the RF power supply, and the arrow turns inopposite directions (upwards and downwards in the drawing) via the uppersurface portion 12.

In one embodiment, a conventional plasma apparatus including threeconstituting elements of an RF power supply (1), matching unit (2), andplasma generation chamber (3) are briefly described. An RF powersupplied from the high-frequency power supply (RF power supply (1))causes mismatching in the matching unit (2) by the vibration of theplasma impedance, and returns as a reflection power whose amplitudevibrates at the high speed to the RF power supply (1). Additionally,since the matching unit (2) cannot follow the vibration speed of theplasma impedance, the reflection cannot be suppressed, and thereflection power causes an automatic matching trouble of the matchingunit (2). As a result, the reflection wave is generated which cannot behandled by the RF power supply (1) or the matching unit (2) and whichhas a value not less than a predetermined value. Under these conditions,a product being manufactured is adversely affected. Therefore, it isnecessary to suppress the generation of plasma instability (high-speedimpedance change of the plasma) in order to manufacture the stableproduct without being influenced. In an embodiment of the presentinvention, the direct-current magnetic field is supplied into the plasmahaving caused the plasma instability, the drift speed of the electronsis reduced or controlled, the deviation on the plasma surface iseliminated, and it is possible to allow the instability to disappear. Inthis manner, an embodiment of the present invention can provide aremarkably effective countermeasure in order to solve the problem of theplasma instability.

In one embodiment of the present invention, a large number of reflectionwaveforms were monitored with the plasma instability seen therein, andvarious data obtained. The data, being studied in detail, is graphicallydisplayed. FIG. 2 shows one example of the data measured and obtainedfrom an embodiment of the present invention, the apparatus having aconstitution including the measurement system apparatus of FIG. 1. FIG.2 shows the data obtained by detecting the reflection power waveforminto the RF power supply during the generation of the plasma instabilitywith a directional coupler of about −63 dB. FIG. 2 shows the vibrationof the reflected wave detected by the directional coupler in a relationbetween time (s) and amplitude (Vpp). As shown in FIG. 2, a reflectionamplitude largely fluctuates with an elapse of time (time interval ofabout 145 kHz). In one embodiment, it was determined that the reflectionwaveform into the RF power supply in the unstable state indicates theinstability of the plasma. In one embodiment, the instability is avibration of plasma impedance, and caused by external factors such asthe instability of the RF power supply.

Deduced reasons for causing the plasma instability are as follows. Thatis, an electron positioned around the plasma is influenced both by an RFmagnetic field (B) change and ion sheath electric field (E) changebetween the plasma and a chamber wall. The electrons alternately drifttoward an angle of direction of the plasma apparatus by the magneticfield (B) and electric field (E) (in a direction vertical to themagnetic field B and electric field E), and are rotated in one directionwith a time average.

This drift rotates the electron around a circular cylinder of theplasma, a non-uniform plasma density change (like a surface wave ofwater) sometimes occurs in the surface of the electron, and thereby theplasma impedance is fluctuated at a frequency relatively lower than anRF frequency. This supposedly causes the instability of the plasma.Therefore, the phenomenon can be resolved by supplying thedirect-current magnetic field to the plasma from the outside. Moreover,when the drift speed of the electrons is controlled, it is possible tocontrol the plasma instability. In embodiments of the present invention,a stabilized plasma apparatus is realized in this manner.

In a plasma apparatus in which a conventional method shown by the dataof FIG. 2 was based, the vibration of the reflection wave was measuredat about 145 kHz. However, under other conditions, a range of about 50kHz to 300 kHz of the vibration of the reflection wave having caused theplasma instability was observed. This range indicates the vibration at aconsiderably high speed. The considerably high speed vibration resultedfrom the plasma impedance at the speed. As described above, the causefor the generation of the plasma instability is supposedly that theelectrons in the surface of a plasma circumference are influenced by themagnetic and electric fields and drift, and that a deviation isgenerated and a standing wave is generated. As a result, it is presumedthat the plasma impedance changes at a high speed of 50 kHz to 300 kHz.

FIGS. 3A and 3B will next be referred to. FIG. 3A shows one embodimentof the plasma apparatus according to the present invention, and is aconstitution diagram showing the basic constituting elements. FIG. 3B isa diagram showing an electric circuit constitution of FIG. 3A. In FIGS.3A and 3B, the object is disposed inside the chamber 10, and is treatedby the generated plasma in the plasma apparatus. The chamber 10 issealed and surrounded with a plurality of members so as to have theinner space. The upper surface portion 12 of the chamber is referred toas a quartz window 12 as a window portion of a dielectric material, andthe entire RF induction coil 20 is disposed outside (above) and in thevicinity of the quartz window 12 (dielectric member).

In FIG. 3A, an RF generator 60 supplies an RF current to the RFinduction coil 20 via a matching network 30. Moreover, a DC power supply50 simultaneously supplies a direct current to the RF induction coil 20via an RF cut filter 40 separated from the DC power supply 50. In oneembodiment, the matching network 30 includes a plurality of capacitorsC2, C4 and variable capacitors C1, C3, and the RF cut filter 40 isconstituted to include coils L2, L3 and a plurality of capacitors C5,C6, C7. Capacitor C7 is connected between the positive terminal of DCpower supply 50 and ground, and capacitor C5 is connected between thenegative terminal of DC power supply 50 and ground. Capacitor C6 isconnected between the positive terminal and the negative terminal of DCpower supply 50.

As shown in FIG. 3A, with the above-described combination of theconstituting elements, essential requirements of the present inventionare satisfied by passing the direct current to the RF induction coil 20or by supplying the direct-current magnetic field to the inner space10′. In a plasma treatment method according to the present invention towhich the direct-current magnetic field is applied, in one embodiment ofthe present invention of FIG. 3A, the RF induction coil is disposed inparallel to the RF power supply, and the direct current is directlysupplied to the coil. In this structure, a TCP coil generates both theRF frequency magnetic field for generating the plasma and thedirect-current magnetic field for stabilizing the plasma.

FIGS. 4A and 4B shows graphs of one example of measured data obtainedfrom the plasma apparatus to which the present invention is applied.FIG. 4A shows a change (Gauss) of the magnetic flux density by adistance (cm) from the RF induction coil during the supplying of adirect current of 36A. With an increase of the distance (cm), themagnetic flux density (coordinate) drops with a movement of a gentlecurve which is inversely proportional and swells downwards. In aposition A of the graph, the magnetic flux density has a value of about4.2 Gausses in a position distant from the coil by 7 cm.

Moreover, FIG. 4B is another graph showing a supplied direct current (A)and the change (Gauss) of the magnetic flux density in a position of 7cm (position A) from the RF induction coil. As shown in FIG. 4B, a valueof magnetic flux density increases substantially proportionally andlinearly.

FIGS. 5A-5C are graphs showing one example of the measured data obtainedby the plasma apparatus to which the present invention is applied. FIG.5A is a graph showing the change of the reflection power (30 mT/SF6150/TCP 250 W/Bias 0 W) to the change of the supplied direct-currentmagnetic field (abscissa), and it is apparent that the reflection powerdecreases with the increase of the direct-current magnetic field.Moreover, FIG. 5B shows that the direct current is not passed withoutapplying the present invention. That is, the graph shows the reflectionwaveform during the supplying of no direct current at a direct-currentmagnetic field of 0 Gauss (direct current of 0 A). Similar to thewaveform shown in FIG. 2, the waveform of FIG. 5B is shown in which theamplitude of the reflection power largely vibrates with an elapse oftime (μs).

With respect to FIG. 5B, FIG. 5C shows that the present invention isapplied and the direct current is passed, and shows the reflectionwaveform during the supplying of a direct-current magnetic field of 4.3Gausses (direct current of 36 A). This shows a strip-shaped waveform inwhich the amplitude of the reflection power does not largely fluctuateeven with a change of a time (μs) axis, and indicates a substantiallyconstant value (normal value). By comparison of data of FIGS. 5B and 5C,it can be confirmed that there is no amplitude fluctuation of thereflection wave in FIG. 5C, and the instability of the plasmadisappears.

As a result of the comparison of the apparatus to which the presentinvention is applied with the apparatus to which the present inventionis not applied, and a verification experiment, when the direct-currentmagnetic field is supplied to the plasma having caused the instabilityfrom the outside, the vibration of the reflection wave into the RF powersupply is found to disappear. That is, the plasma instabilitydisappears.

When the method of supplying the direct-current magnetic field accordingto the present invention is applied, the method of simultaneouslysuperimposing and passing the direct current from the direct-currentpower supply to the existing inductively coupled coil in parallel to theRF current is used as described above. The concrete apparatusconstitution of the method is clearly shown by the plasma apparatus inFIGS. 1 and 3A.

Additionally, as a method of obtaining the direct-current magneticfield, in addition to the method of directly passing the direct currentto the RF induction coil as described above, various methods of formingthe direct-current magnetic field are considered. The concreteconstitution will be described with reference to FIG. 6. According tothe constitution, a coil for forming the direct-current magnetic fieldmay be used and disposed in any one of the periphery (side surface),upper surface portion, and bottom surface portion of the chamber of theapparatus. Alternatively, an electromagnet or permanent magnet forsupplying the direct-current magnetic field may also be used anddisposed in the periphery (side surface), upper surface portion, andbottom surface portion of the chamber.

FIGS. 6A-6D show diagrams of additional embodiments of the plasmaapparatus in accordance with the present invention, and show schematicconstitution diagrams of various direct-current magnetic field supplymethods.

FIG. 6A shows an embodiment in which an air-core coil 90 for thedirect-current magnetic field is disposed around (outside) the chamber10. The air-core coil 90 for the direct-current magnetic field isdisposed outside the side surface portion 11 close to an upper surfaceportion 12 side which contacts the RF induction coils 20. According tothe structure of the apparatus, a direct-current magnetic flux (Φ_(DC))flows through the inner space of the chamber 10.

Next, FIG. 6B shows an embodiment in which the air-core coil 90 for thedirect-current magnetic field is disposed above the upper surfaceportion 12 of the chamber 10. The coils 90 are disposed on left andright sides of the RF coils 20 which contact the upper surface portion12 in an arrangement structure. Even with the structure of theapparatus, the direct-current magnetic field (Φ_(DC)) flows in the innerspace of the chamber 10.

FIGS. 6C and 6D show embodiments of the present invention in which amagnet for the direct-current magnetic field is disposed around thechamber 10. In a left-side structure 3-a of FIG. 6C, a magnet member 91is disposed outside the side surface portion 11 of the chamber 10, andthereby the direct-current magnetic field (Φ_(DC)) is generated andpassed through the inner space of the chamber 10. Moreover, in aright-side structure 3-b of FIG. 6C, a magnet member 92 is used anddisposed over the side surface 11 of the chamber 10, and thedirect-current magnetic field (Φ_(DC)) is generated and passed into theinner space from the upper surface portion 12 and bottom surface portion13. In the structures of (III) and (IV), the direct-current magneticfield (Φ_(DC)) flows in the inner space of the chamber 10.

Moreover, in FIG. 6D, the magnet members 91, 92 for the direct-currentmagnetic field illustrated in FIG. 6C are replaced with electromagnets93, 94, and the structure illustrated in FIG. 6C is basically similar tothat illustrated in FIG. 6D. The electromagnet 94 includes a solenoidcoil 94 a and core 94 b (such as iron and ferrite) extending from theinside of the coil. The core 94 b extending over the side surfaceportion 11 of the chamber 10 generates and supplies the direct-currentmagnetic field (Φ_(DC)) into the inner space from the upper surfaceportion 12 and bottom surface portion 13.

The plasma stabilization method and plasma apparatus according to thepresent invention are used in technical fields of apparatus related tothe plasma, such as a semiconductor manufacturing apparatus using theplasma, material manufacturing apparatus using the plasma, fineprocessing apparatus using the plasma, and surface treatment apparatususing the plasma. When embodiments of the present invention are appliedto these apparatuses, very superior effects are obtained.

Moreover, when the direct-current magnetic field is applied according toembodiments of the present invention, the plasma is stabilized andcontrolled. Additionally, the present invention is expected to beapplied to techniques of controlling a plasma density and of controllingunevenness and process ratio, and future usability and effect are large.

According to embodiments of the present invention, an originalinstability of plasma can technically be clarified and resolved. Whenhardware having a simple structure is added, a stabilized plasma can berealized. Moreover, in an embodiment of a plasma apparatus including theinductively coupled coils such as ICP and TCP, there is provided astructure in which the direct-current magnetic field can remarkablyeasily be applied according to the present invention, and practicabilityis high. Moreover, the carrying out of the present invention providesmany industrial advantages that the structure can be compact, space isreduced, cost does not increase, and small investment is possible.

As described above, according to the plasma stabilization method andplasma apparatus of the present invention, when the direct-currentmagnetic field is applied to an actual manufacturing process, theinstability of the plasma (change/fluctuation of the high-speedimpedance of the plasma) is removed, and the stabilized plasma apparatuscan be realized. Moreover, in the present invention, since the structureof the plasma apparatus is remarkably simple. Therefore, the apparatusis actually applied, the compact constitution can be used as suchwithout increasing the cost.

What is claimed is:
 1. A plasma processing system, comprising: aprocessing chamber operable to process an object disposed within theprocessing chamber; a surrounding member disposed so as to surround theprocessing chamber, the surrounding member including a top surface, aside surface, and a bottom surface that create an inner space, the topsurface being a dielectric member sealing an opening on top of theprocessing chamber; an RF induction coil disposed above the top surface;a direct-current magnetic field generator for supplying a direct-currentmagnetic field to the inner space; and an RF cut filter connected to adirect current (DC) power supply and connected to the direct-currentmagnetic field generator, the RF cut filter including a first capacitorconnected to a positive terminal of the DC power supply and to groundand a second capacitor connected to a negative terminal of the DC powersupply and to ground.
 2. The plasma processing system of claim 1,wherein the direct-current magnetic field extends along a direction froma first side of said surrounding member toward a second side of saidsurrounding member disposed opposite to said first side, with saiddirect-current magnetic field having a magnitude to control reflectionof RF energy inductively coupled to said inner space.
 3. The plasmaprocessing system of claim 1, a magnitude of said direct-currentmagnetic field being established to control reflection of RF frequencygenerated by the RF induction coil from said inner space.
 4. The plasmaprocessing system of claim 1, wherein the direct-current magnetic fieldgenerator is a structure operable to supply the direct-current magneticfield to the inner space, wherein the structure is a coil separate fromthe RF induction coil, and wherein the structure is not a magnet.
 5. Theplasma processing system of claim 1, wherein the direct-current magneticfield generator is an air-core coil disposed outside and above the topsurface.
 6. The plasma processing system of claim 5, wherein theair-core coil is operable to generate the direct-current magnetic fieldwhen a direct current is passed through the air-core coil.
 7. The plasmaprocessing system of claim 6, wherein the direct current is constitutedsuch that a quantity of the direct current can be varied.
 8. The plasmaprocessing system of claim 6, wherein the direct current is constitutedsuch that a polarity of the direct current can be varied.
 9. The plasmaprocessing system of claim 5, wherein the RF cut filter is connected toa first end and to a second end of the air-core coil.
 10. The plasmaprocessing system of claim 9, wherein the RF cut filter further includesa third capacitor connected between the positive terminal and thenegative terminal of the DC power supply.
 11. A plasma processingsystem, comprising: a processing chamber operable to process an objectdisposed within the processing chamber; a surrounding member disposed soas to surround the processing chamber, the surrounding member includinga top surface, a side surface, and a bottom surface that create an innerspace, the top surface being a dielectric member sealing an opening ontop of the processing chamber; an RF generator; a matching networkconnected to the RF generator; an RF induction coil connected to thematching network and disposed above the top surface; a direct-currentmagnetic field generator for supplying a direct-current magnetic fieldto the inner space; and an RF cut filter connected in parallel to the RFinduction coil and the matching network, the RF cut filter connected toa direct current (DC) power supply and connected to the direct-currentmagnetic field generator, the RF cut filter including a first capacitorconnected to a positive terminal of the DC power supply and to ground, asecond capacitor connected to a negative terminal of the DC power supplyand to ground, and a third capacitor connected to the positive terminaland to the negative terminal of the DC power supply.
 12. The plasmaprocessing system of claim 11, wherein the direct-current magnetic fieldgenerator is a structure operable to supply the direct-current magneticfield to the inner space, wherein the structure is a coil separate fromthe RF induction coil, and wherein the structure is not a magnet. 13.The plasma processing system of claim 11, wherein the direct-currentmagnetic field generator is an air-core coil disposed outside and abovethe top surface.